1. Field of the Invention
This invention relates to improvements to harvesters in particular sugar cane harvesters.
2. Description of the Related Art
Conventional cane harvesters normally include a forwardly extending topper mechanism which is adapted to cut the tops from cane prior to the cane being gathered by the harvester. Cane harvesters also include a base cutter assembly for cutting the cane at its base and a chopper mechanism which cuts the harvested cane into billets and directs the cane billets onto a primary elevator for transport to a secondary elevator so that the cane billets can be deposited in a collection bin or the like. Many machines also incorporate blowers so that trash collected by the harvesters can be blown through a discharge chute at the rear of the machine.
The above known machines suffer a number of disadvantages. Firstly in some harvesters the topper mechanism tends to direct the cut cane tops into the path of the harvester particularly where crosswinds are blowing. This consequently results in the harvester collecting extraneous material and loss of commercial cane sugar. To overcome this disadvantage, some topper mechanisms employ rotating vanes mounted above the topper cutting disc which pelt the cut tops of the cane outwardly to either side of the harvester. Whilst this arrangement usually ensures that the cane tops are not collected by the harvester, a danger is obviously created to people working in the area such as bin haul-out drivers.
A further disadvantage in the known harvesters occurs when sugar cane that has fallen over as a result of wind or heavy rain, or standover cane is to be harvested. In such instances, there is an uneven feed of cane to the chopping mechanism resulting in an uneven deposit of cane on the primary elevator. As a consequence an uneven flow of the chopped-up material has to be handled by the blower which can cause blockages in the trash discharge system. Furthermore, the deposit of billets into the secondary elevator in such circumstances tends to be uneven and often the trash is not clearly stripped from the billets.
U.S. Pat. No. 2,395,089 to Arelt discloses a levelling device for tobacco comprising a series of parallel vanes arranged above a vibrating plate which serves to convey the tobacco. Whilst this type of device is suitable for tobacco type products, it is not suitable for application to cane harvesters where it is necessary to strip leaves from cane billets and where cane billets move along the conveyor in clumps.